Covers for cotton bales have heretofore been constructed utilizing a woven jute construction. Such covers possess disadvantages in that they are relatively expensive and tend to contaminate the cotton with the jute fibers. Efforts to supply cotton bale covers having improved characteristics are illustrated in U.S. Letters Pat. Nos. 3,647,061 and 3,674,139. Such covers are of laminated construction however, and tend to be expensive, presenting further problems in that they are not sufficiently air permeable when the cotton is compressed for baling and tend to cause mildew. Ring spun yarn is impractical for use in the present application because of the high level of defects in the yarn making warp knitting impractical. By the use of open end spinning, it is possible to use a lower grade of cotton for the courser yarn counts and yet produce yarn of acceptable quality for warp knitting. Such fabrics may be made to any desired width and possess a true selvage. It is thus possible to produce a yarn consisting essentially of cotton and suitable to be used on warp knitting equipment for constructing a bale cover.
Normally, course yarn counts are not run on warp knitting machines especially when such yarns are constructed of lower quality fiber. Having determined that it is possible to run such yarn on warp knitting machines, it is necessary to find a stitch construction to meet the requirements of a bale cover. A construction similar to a construction normally utilized in trico shirting has been found to produce a satisfactory cover. Cotton bale covers must maintain their shape and be substantially ravel proof so that the compressed bale will not deteriorate excessively, or the fiber of the bale contaminated, when the cover is cut for cotton sampling. In this connection in most warp knit fabrics, all ends are form connected whereas in woven fabrics, the ends are friction connection. Such constructions utilizing course yarn counts provide suitable cover or opacity to protect and retain the fiber mass of the bale in compression. The yarns tend to keep separated maintaining spacing with less tendency for the yarns to bunch together. Moreover, such construction permits a design for balanced tear and tensile strength in both directions without overuse of one to achieve the other.
Accordingly, it is an important object of this invention to produce a cover of light weight material which is warp knit so as to possess stretchability, making for a neater bale and possessing suitable absorption properties to avoid mildew.
Another important object of the invention is to produce a bale cover which is substantially ravel proof and possesses a balance of stretch characteristics in both directions.
Another object of this invention is to provide a bale cover which produces when processed as waste a fiber compatible for use in a variety of applications.